Q. 43.9( 16 Votes )

A plane electromagnetic wave travels in vacuum along z-direction. What can you say about the directions of its electric and magnetic field vectors? If the frequency of the wave is 30 MHz, what is its wavelength?

Class 12th NCERT - Physics Part-I 8. Electromagnetic Waves

Answer :

Given: The electromagnetic wave travels in vacuum along z-direction

The direction of electric field vector and magnetic field vector will be in XY plane.

Frequency of the wave = 30 MHz

Converting into Hz, v = 30× 10⁶ Hz.

Wavelength of the wave can be calculated using the following relation:

λ = c/v

⇒

⇒λ = 10 m

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